I must have missed that Missive
How do I create an alias for my XMR address?
It is done through DNS, so you add a record to your domain. If don't have a domain, get one through your favorite DNS registrar. Simplewallet will decode these so you can type "transmit 3 donate.monero.cc 100" and it will go to the project donation fund.
Example:
donate.monero.cc. 300 IN TXT "oa1:xmr recipient_address=46BeWrHpwXmHDpDEUmZBWZfoQpdc6HaERCNmx1pEYL2rAcuwufPN9rXHHtyUA4QVy66qeFQkn6sfK8aHYjA3jk3o1Bv16em\; recipient_name=Monero Development\; tx_description=Donation to Monero Core Team\;"
donate.monero.cc. 300 IN TXT "oa1:btc recipient_address=1FhnVJi2V1k4MqXm2nHoEbY5LV7FPai7bb\; recipient_name=Monero Development\; tx_description=Donation to Monero Core Team\;"
More info (including information about privacy and security issues): https://openalias.org/